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Math and science::Analysis::Tao::08. Infinite sets

Countable sets

A set \( X \) is said to be countably infinite (or just countable) iff [...]. 

We also have the terms: at most countable and uncountable.

  • A set is at most countable if it is [...].
  • A set is uncountable if it is [...].
The relationship is shown below: